According to Byron York’s reporting in the Washington Examiner, Bush's camp simply believed this would be 1999 all over again. Republican politicians, campaign and governing professionals, formal party officials and staff, donors and activists, and party-aligned media and interest groups, faced with a rare lack of a natural front-runner, would rapidly rally around the tried-and-trusted Bush banner. By the time of his official announcement, which is scheduled for next week, Jeb was supposed to be the consensus candidate.

Why hasn't that happened? As York points out, it isn't just about a poorly organized campaign (a staff shakeup is in progress), or about Bush’s stumbles when talking about Iraq.

As far as I can see -- and we can’t always see everything happening during the "invisible campaign" -- it comes down to Bush's failure to give Republican party actors any good reason to support him.

But having never understood why important party actors, beginning with big-state governors, were so enthusiastic about George W. Bush back in 1999, I may not be the most reliable judge of Jeb’s theoretical appeal this time. And I don't want to overstate this: Bush, Marco Rubio and Scott Walker remain the top tier among Republican presidential candidates, and we still have insufficient information to distinguish among them. If Bush gets a public-opinion surge -- say, if he’s the perceived winner of an early debate -- a lot of on-the-fence Republican party actors might jump on board.

The problem for Bush, however, remains that his appeal is as a safe choice. Other candidates also qualify in that category, while a fair portion of the party has no interest in choosing a safe choice. At the same time, little evidence suggests that nominating another Bush would be all that safe in the first place. It isn't as if national head-to-head polls hint that he would be particularly strong against Hillary Clinton, or that Republicans have any reason to believe Jeb Bush will prove to be a long-term winner for them even if he is elected.

After a few difficult cycles, the Republican Party has a deep, strong field of candidates -- the strongest group since 1988 or even 1980. Just being acceptable is unlikely to cut it in 2016.

Sure, those early polls aren't worth a lot; lots of rank-and-file voters skeptical about a candidate now will adore him if he's nominated. Not all party actors know that, however, and plenty of them are swayed by (otherwise) meaningless polls.

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